Longitude: 0.38, Latitude: 20.38
These are three plugs up to 300 m in diameter one of which consists of phonolite and the other two of eudialyte-nepheline syenite intruding phonolite.
LIEGOIS, J.P., SAUVAGE, J.F. and BLACK, R. 1991. The Permo-Jurassic alkaline province of Tadhak, Mali: geology, geochronology and tectonic significance. Lithos, 27: 95-105.